Concurrent GOLD and SABER Observations of Thermosphere Composition and Temperature Responses to the April 23–24, 2023 Geomagnetic Storm
Year: 2025
Type: article
Abstract: The Global‐scale Observations of Limb and Disk (GOLD) and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instruments were used to investigate the thermospheric composition and temperature responses to the geomagnetic storm on 23–24 April, 2023. Global‐scale Observations of Limb and Disk observed a faster recovery of thermospheric column density ratio of O to N2 (ΣO/N2) in the southern hemisphere (SH) after the storm ended at 12 Universal time (UT) on 24 April. After 12 UT on 25 April, ΣO/N2 had mostly recovered in both hemispheres. Global‐scale Observations of Limb and Disk also observed an increase of middle thermospheric temperature (140–200 km) (Tdisk) on 24 April with a maximum of 340 K. Within 4–6 hr of the storm ending on 24 April, Tdisk enhancement persisted between 30°N and 60°N, 100°W and 30°W, while Tdisk lower than pre‐storm quiet day (17 April) was observed between 45°W and 15°W, 40°S and 50°N. Tdisk recovered between 100°W and 45°W, 30°N and 55°S. On 25 April, Tdisk was lower than on 17 April across the entire GOLD Field‐of‐Regard (FOR) by ∼50–110 K. Additionally, solar irradiance decreased by 15%–20% from 17 to 25 April, indicating that the lower Tdisk on 25 April resulted from both storm and solar irradiance variations. Latitudinal variations of Tdisk and the SABER observed Nitric Oxide (NO) cooling rate revealed that NO cooling is crucial for the lower Tdisk in the northern hemisphere (NH) mid‐high latitudes on 25 April. These results provide direct evidence of decreased thermospheric temperature during storm recovery phase than pre‐storm quiet times.
DOI: 10.1029/2025ja033912
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Awards: G1275415351, SUBAURORAL POLARIZATION STREAMS (SAPS) ARE A LATITUDINALLY NARROW BAND OF HIGH-SPEED PLASMA DRIFTS OCCURRING MOSTLY IN THE AFTERNOON TO MIDNIGHT SECTOR. THEY ARE LOCATED IN A REGION THAT IS JUST OUTSIDE OF THE AURORAL OVAL OF ELECTRON PRECIPITATION WHERE THE DOWNWARD REGION-2 CURRENTS FROM THE INNER MAGNETOSPHERE FLOW THROUGH THE LOW IONOSPHERIC CONDUCTIVITY REGION OF MIDDLE LATITUDE PLASMA DENSITY TROUGH AND ARE CLOSED BY THE UPWARD REGION-1 CURRENTS TO THE MAGNETOSPHERE IN THE AURORAL OVAL. THIS REGION IS THUS THE DYNAMIC INTERFACE OF DIFFERENT REGIMES OF THE COUPLED MAGNETOSPHERE IONOSPHERE THERMOSPHERE (M-I-T) SYSTEM. COMPLEX PHYSICAL PROCESSES OF DIFFERENT TEMPORAL AND SPATIAL SCALES OCCUR IN THIS REGION. A FULL DESCRIPTION OF THE FUNDAMENTAL PHYSICAL PROCESSES THAT GOVERN THE OCCURRENCE CHARACTERISTICS VARIATIONS AND EFFECTS OF SAPS IS STILL ELUSIVE AND CHALLENGING BECAUSE IT REQUIRES A SYSTEMATIC APPROACH INVOLVING HIGH-RESOLUTION FIRST PRINCIPLES SIMULATIONS AND COMPREHENSIVE OBSERVATIONS OF THE ENTIRE M-I-T SYSTEM. THESE MODELING AND OBSERVATIONAL CAPABILITIES HAVE NOT BEEN AVAILABLE UNTIL RECENTLY. HERE WE PROPOSE TO EXPLORE AND UNDERSTAND THESE PHYSICAL PROCESSES THEIR CHANGES WITH SOLAR WIND AND GEOPHYSICAL CONDITIONS AND THEIR EFFECTS ON THE M-I-T SYSTEM THROUGH NUMERICAL SIMULATIONS AND MODEL-DATA COMPARISONS. THIS GOAL WILL BE ACHIEVED BY ADDRESSING THE FOLLOWING SCIENTIFIC QUESTIONS: 1) HOW DO SAPS CHANGE WITH SOLAR WIND AND GEOPHYSICAL CONDITIONS? 2) WHAT ARE THE EFFECTS OF SAPS ON THE GLOBAL I-T SYSTEM? 3) WHAT ARE THE FEEDBACK EFFECTS OF THE I-T CHANGES DURING SAPS EVENTS ON M-I COUPLING AND THE MAGNETOSPHERE?, G2754602250, EARTHS THERMOSPHERE AND IONOSPHERE ARE STRONGLY INFLUENCED BY THE ENERGY AND MOMENTUM INPUT FROM THE MAGNETOSPHERE. THIS INPUT GREATLY DEPENDS ON SOLAR WIND AND INTERPLANETARY MAGNETIC FIELD (IMF) CONDITIONS THAT DETERMINES HIGH-LATITUDE IONOSPHERIC CONVECTIVE ELECTRIC FIELDS PARTICLE PRECIPITATION AND JOULE HEATING. IN PREVIOUS WORK THERMOSPHERIC TEMPERATURE WINDS AND COMPOSITION HAVE BEEN PRIMARILY STUDIED UNDER GEOMAGNETICALLY ACTIVE PERIODS DRIVEN BY SOUTHWARD INTERPLANETARY MAGNETIC FIELD CONDITIONS. HOWEVER THERE ARE MANY CASES WHEN THE IMF BY COMPONENT IS COMPARABLE OR LARGER THAN THE BZ COMPONENT. IN THESE CASES THE HIGH-LATITUDE CONVECTION PATTERN AND PRECIPITATION BEHAVE VERY DIFFERENTLY FROM THEIR BEHAVIOR WHEN IMF BZ IS DOMINANT. THE ENERGY AND MOMENT INPUTS FROM THE MAGNETOSPHERE AND THEIR EFFECTS ON THE STATE OF THE THERMOSPHERE AND IONOSPHERE WHEN IMF BY IS LARGE ARE ALSO VERY DIFFERENT. TO DATE THERE HAVE BEEN VERY FEW STATISTICAL AND EVENT STUDIES OF THE THERMOSPHERIC COMPOSITION CHANGES DURING IMF BY DOMINANT CONDITIONS. THIS IMPAIRS OUR UNDERSTANDING OF HOW THERMOSPHERIC COMPOSITION CHANGES DURING VARIOUS GEOPHYSICAL CONDITIONS THE PHYSICAL MECHANISM BY WHICH THESE CHANGES OCCURS AND THEIR EFFECTS ON THE IONOSPHERE. HERE WE PROPOSE TO ADDRESS THIS ISSUE BY USING NUMERICAL SIMULATIONS AND TIMED GUVI O/N2 COMPOSITION DATA TO UNDERSTAND GLOBAL STRUCTURES OF THERMOSPHERIC COMPOSITION ASSOCIATED WITH IMF BY DOMINANT CONDITIONS AND THE IONOSPHERIC DISTRIBUTIONS RELATED TO THESE CONDITIONS. THIS GOAL WILL BE ACHIEVED BY ADDRESSING THE FOLLOWING SCIENTIFIC QUESTIONS: 1) ARE THE GLOBAL STRUCTURES OF THERMOSPHERE COMPOSITION SIGNIFICANTLY DIFFERENT WHEN THE IMF BY IS LARGE? 2) DO THESE STRUCTURES CHANGE WITH SEASON AND SOLAR CYCLE? 3) ARE OTHER THERMOSPHERIC FIELDS AND THE IONOSPHERE ALSO RESPONSIVE TO IMF BY? THE TIMED GUVI O/N2 AND NO DATA AND THE COUPLED MAGNETOSPHERE IONOSPHERE AND THERMOSPHERE (CMIT) MODEL A FIRST PRINCIPLES MODEL OF THE COUPLED MAGNETOSPHERE IONOSPHERE AND THERMOSPHERE SYSTEM WILL BE USED TO ADDRESS THESE QUESTIONS. MODEL SIMULATIONS WILL BE USED TO INTERPRET SATELLITE OBSERVATIONS AND TO OBTAIN PHYSICAL INSIGHT ABOUT THE FORCES CAUSING COMPOSITION CHANGES DURING IMF BY DOMINANT CONDITIONS. BY DEVELOPING AN UNDERSTANDING OF THREE-DIMENSIONAL VARIATIONS OF THERMOSPHERIC COMPOSITION UNDER THESE CONDITIONS THIS PROPOSAL WILL PROVIDE CONTEXT FOR THE UPCOMING NASA ICON AND GOLD MISSIONS. THE IMF DATA WILL BE OBTAINED FROM THE NASA CDAWEB. THIS PROPOSED WORK USES DATASETS FROM THE ONGOING HELIOPHYSICS MISSION TIMED AND A STATE-OF-ART PHYSICS-BASED NUMERICAL MODEL. IT FITS THE KEY REQUIREMENT OF THE NASA HSR PROGRAM: TO EMPLOY A COMBINATION OF SCIENTIFIC TECHNIQUES THAT INCLUDE BOTH NUMERICAL SIMULATION AND DATA ANALYSIS AND INTERPRETATION OF NASA-SPACECRAFT OBSERVATIONS. THE PROPOSED STUDY CLOSELY ADDRESSES TWO OF THE FOUR HIGH LEVEL SCIENCE GOALS OF THE HELIOPHYSICS DECADAL SURVEY: DETERMINE THE DYNAMICS AND COUPLING OF EARTH S MAGNETOSPHERE IONOSPHERE AND ATMOSPHERE AND THEIR RESPONSE TO SOLAR AND TERRESTRIAL INPUTS ; AND DISCOVER AND CHARACTERIZE FUNDAMENTAL PROCESSES THAT OCCUR BOTH WITHIN THE HELIOSPHERE AND THROUGHOUT THE UNIVERSE ., (A) KEY OBJECTIVES AND THEIR SCIENTIFIC IMPORTANCE THE KEY OBJECTIVES OF THE PROPOSED WORK ARE TO DETERMINE THE CHARACTERISTICS OF THE STORM-TIME TOP, SEASONAL CHANGES ARE ONE OF THE MAIN DYNAMICAL FEATURES OF THE EARTHS UPPER ATMOSPHERE. THE STATE OF THE THERMOSPHERE AND IONOSPHERE AT THE WINTER SOLSTICE IS VERY DIFFERENT FROM THE STATE AT THE SUMMER SOLSTICE. TO GET FROM ONE STATE TO ANOTHER REQUIRES A TRANSITION NEAR THE EQUINOX. SURPRISINGLY WE KNOW VERY LITTLE ABOUT HOW THIS TRANSITION OCCURS YET THERE IS GROWING EVIDENCE THAT IT IS FAR FROM THE SIMPLE ANNUAL SINUSOID THAT IT IS OFTEN ASSUMED TO BE. THEREFORE WE PROPOSE TO UNDERTAKE A SERIES OF STUDIES TO ELUCIDATE THE NATURE OF THE EQUINOX TRANSITION USING TIMED-GUVI (THERMOSPHERE IONOSPHERE MESOSPHERE ENERGETICS AND DYNAMICS GLOBAL ULTRAVIOLET IMAGER) DATA TO DETERMINE THE BEHAVIOR OF O/N2 NEAR AT THE EQUINOXES. PRELIMINARY STUDIES USING GUVI DATA HAVE SHOWN THAT THE NUMBER OF DAYS THAT O/N2 SPENT IN AN EQUINOX STATE (WITH MAXIMUM O/N2 AT THE EQUATOR RATHER THAN IN THE MIDDLE LATITUDES) IS SHORT. SIMILARLY RAPID EQUINOX TRANSITIONS HAVE BEEN SEEN IN THE TOPSIDE IONOSPHERE WHICH IS CONNECTED TO O/N2 AS A RESULT OF THE F2 REGION IONOSPHERE BEING CREATED BY THE BALANCE BETWEEN THE IONIZATION OF O AND RECOMBINATION THROUGH CHEMICAL REACTIONS BETWEEN O+ AND N2 AND O2. TOPSIDE IONOSPHERE DATA ALSO SUGGEST THAT THERE ARE FUNDAMENTAL DIFFERENCES IN THE BEHAVIOR OF THE IONOSPHERE BETWEEN THE SEPTEMBER EQUINOX AND THE MARCH ONE. STUDYING THIS BEHAVIOR IS IMPORTANT FOR A NUMBER OF REASONS. FIRST BOTH DATA ANALYSIS AND MODELING STUDIES OFTEN LUMP THE 3 MONTHS AROUND THE EQUINOX TOGETHER PRODUCING TWO-PEAKED BEHAVIOR AROUND THE EQUATOR WHEN THE ACTUAL BEHAVIOR MAY BE MASKED OR CONTAMINATED BY TWO SOLSTICE SEASONS. SECOND THE RAPID TRANSITION HAS A DIRECT IMPACT ON OUR UNDERSTANDING OF IONOSPHERE-THERMOSPHERE PHENOMENA SUCH AS THE IONOSPHERIC WINTER ANOMALY BUT THIS IMPACT IS AS YET POORLY UNDERSTOOD. WE PROPOSE A SERIES OF STUDIES TO ENABLE US TO BETTER UNDERSTAND THE NATURE OF THE EQUINOX TRANSITION OF O/N2 AND THE CAUSES OF ITS VARIABILITY: 1. DOES THE LENGTH OF THE EQUINOX TRANSITIONS CHANGE FROM YEAR-TO-YEAR IN O/N2 DATA?2. ARE THE DIFFERENCES IN THE O/N2 EQUINOX TRANSITION BETWEEN MARCH AND SEPTEMBER CONSISTENT FROM YEAR TO YEAR? 3. WHY IS THERE AN EQUATORIAL PEAK IN O/N2 DURING THE MARCH EQUINOX? 4. HOW DOES THIS TRANSITION IN O/N2 NEAR THE EQUINOXES IMPACT THE IONOSPHERE? THESE QUESTIONS WILL BE ADDRESSED PRIMARILY BY USING THE CURRENT DATABASE OF GUVI MEASUREMENTS OF THE HEIGHT-INTEGRATED O/N2 RATIOS. A THEORETICAL BACKGROUND FOR THESE STUDIES WILL BE PROVIDED BY THE NCAR-TIEGCM (NATIONAL CENTER FOR ATMOSPHERIC RESEARCH THERMOSPHERE-IONOSPHERE-ELECTRODYNAMICS GENERAL CIRCULATION MODEL). ADDITIONAL OBSERVATIONAL DATA FROM GROUND BASED TOTAL ELECTRON CONTENT AND IONOSONDE OBSERVATIONS OF F PEAK DENSITIES WILL BE USED. THE PROPOSED WORK ADDRESSES PART OF THE PRIMARY GOAL OF THE CURRENT NASA TIMED FLIGHT MISSION AS WELL AS THE BASIC STRUCTURE (I.E. PRESSURE TEMPERATURE AND WINDS) THAT RESULTS FROM THE ENERGY TRANSFER INTO THE REGION (DYNAMICS) . IT ALSO RELATES TO TWO OF THE FOUR AREAS OF THE DECADAL SURVEY (2 AND 4). IT IS CENTRAL TO DETERMINING THE DYNAMICS OF THE EARTH S UPPER ATMOSPHERE TO UNDERSTAND HOW AND WHY COMPOSITION VARIES IN THIS HETEROGENEOUS REGION (2). THE WAY THAT THE THERMOSPHERIC CHANGES THROUGH THE EQUINOXES AND UNDERSTANDING THE CAUSES OF THIS CHANGE IS ALSO A FUNDAMENTAL PROCESS THAT IS AS YET POORLY UNDERSTOOD (4). THE PROPOSED WORK WILL ALSO ENABLE US TO BETTER UNDERSTAND THE CAUSES OF COMPOSITION CHANGES AND HELP TO PROVIDE A CONTEXT FOR THE FORTHCOMING NASA GOLD (GLOBAL-SCALE OBSERVATIONS OF THE LIMB AND DISK) AND ICON (IONOSPHERIC CONNECTION EXPLORER) FLIGHT MISSIONS., G3684050704, Collaborative Research: Understanding the Quiet Time Thermospheric Composition Contribution to Ionospheric Day-to-Day Variability over the American Continent, G3994111646, G4144199136, G4672550800, CARBON DIOXIDE IS INCREASING THROUGHOUT THE ATMOSPHERE, BUT THE RECENT FINDING THAT IT IS INCREASING FASTER NEAR AND ABOVE THE MESOPAUSE THAN IN THE, G7896376814, G8201607002, G8924287671, G8963087954
OpenAlex ID: W4409456188